CN106483381B - Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method - Google Patents

Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method Download PDF

Info

Publication number
CN106483381B
CN106483381B CN201610884614.XA CN201610884614A CN106483381B CN 106483381 B CN106483381 B CN 106483381B CN 201610884614 A CN201610884614 A CN 201610884614A CN 106483381 B CN106483381 B CN 106483381B
Authority
CN
China
Prior art keywords
voltage source
electric current
current
variable voltage
additive error
Prior art date
Application number
CN201610884614.XA
Other languages
Chinese (zh)
Other versions
CN106483381A (en
Inventor
王晓俊
李建宇
陈涛
葛颖森
牛丹
赵永杰
Original Assignee
东南大学
南京长盛仪器有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 东南大学, 南京长盛仪器有限公司 filed Critical 东南大学
Priority to CN201610884614.XA priority Critical patent/CN106483381B/en
Publication of CN106483381A publication Critical patent/CN106483381A/en
Application granted granted Critical
Publication of CN106483381B publication Critical patent/CN106483381B/en

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/025Measuring very high resistances, e.g. isolation resistances, i.e. megohm-meters
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01RMEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
    • G01R27/00Arrangements for measuring resistance, reactance, impedance, or electric characteristics derived therefrom
    • G01R27/02Measuring real or complex resistance, reactance, impedance, or other two-pole characteristics derived therefrom, e.g. time constant
    • G01R27/14Measuring resistance by measuring current or voltage obtained from a reference source

Abstract

The invention discloses a kind of superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method, described device includes signal source output, relay switch, relay switch, current-to-voltage converting circuit, tension measuring circuit, controller and the asymmetric double of two-way complementation polarity precision variable voltage source;The method sets driving voltage as 0V and relay switch first, then two-way asymmetric double polarity precision variable voltage source is adjusted according to the asymmetric adjusting algorithm of micro-current by controller, until the output valve of tension measuring circuit is less than given threshold, compensated additive error electric current is calculated then according to the output valve of tension measuring circuit, last closing relay switch carries out the leakage current after actual measurement and the additive error electric current that is eliminated according to backoff algorithm.The present invention solves the accurate compensation problem of small additive error electric current, significantly improves superelevation insulation measurement resolution ratio, range and consistency.

Description

Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method

Technical field

The present invention relates to a kind of insulation resistance measuring device and methods more particularly to a kind of superelevation insulation measurement instrument to use The compensation device and method of additive error electric current.

Background technique

Insulation measurement is the important content of electrical safety measurement, and insulation measurement is generally by detected element Both ends apply test voltage Us, measure the electric current I flowed through in detected elements, further according to formula R=Us/IsRealize the indirect of resistance Measurement.Superelevation insulation measurement instrument is measurement magnitude 1012The measuring device of Ω or more resistance, traditional super high resistance measurement according to Lai Yu promotes test voltage, and such as 5kV, 10kV or higher, the purpose is to guarantee the electric current for flowing through detected element in nA or uA or more. This measurement scheme is in this kind of insulation performance test for being difficult to apply 100V or more high voltage of the high insulation film capacitor of such as low pressure It is difficult to be applicable in, how to realize that superelevation insulation measurement under low pressure has become one of modern electrical safety fields of measurement Problem.

The essence of superelevation insulation measurement is the electric current I that detection flows through detected elements.But practical flow into is tested member The electric current of part does not comprise only effect leakage current, further includes the additive error electric current for measuring loop.Under the conditions of low test voltage, Effective leakage current of superelevation insulation resistance element is generally pA grades, is even less than sub- pA grades of 1pA, effectively leakage is electric at this time Down to close with additive error electric current, measurement error dramatically increases flow value, so that be difficult to meet actual measurement accuracy demand; Therefore in low pressure superelevation insulation measurement application, additive error electric current is extension insulation measurement range, improves and stablize The important bottlenecks of property and consistency.

The additive error electric current of superelevation insulation measurement instrument measurement loop is let out mainly from the background of measuring circuit itself Leakage current, fixture and detected element contact thermoelectrical potential and leader cable caused by leakage current, fixture electrical network distribution parameter Extra current caused by friction electricity etc., total additive error electric current is frequently more than 10pA or more.Such as the low-pressure membrane of height insulation Capacitor, insulation resistance is frequently more than 1T Ω, and test condition is usually in 10V hereinafter, effective leakage current is only at this time 10pA, and the additive error current amplitude for measuring loop has been approached or more than tested thin-film capacitor itself leakage current, how Eliminating or inhibiting the error influence of background current is the key that accurately to measure.

Commercialization Insulation Resistance Tester is attached by applying compensating current element progress all the way at input electric cur- rent measure end at present Error current is added to compensate, this method has good compensation effect in nA or more current detecting, but when additive error electric current is lower than When nA, because the signal-to-noise ratio of compensating current element output electric current is low, it is difficult to meet the compensation demand of micro- error current.

Summary of the invention

Goal of the invention: in order to overcome the deficiencies in the prior art, the present invention uses two-way asymmetric complementary current source It carries out additive error current compensation and passes through two-way high s/n ratio current source output signal when additive error electric current is small Subtract each other to form compensation electric current, solve the accurate compensation problem of small additive error electric current, to significantly improve the survey of superelevation insulation resistance Measure resolution ratio, range and consistency.

Technical solution: to achieve the above object, the technical solution adopted by the present invention are as follows:

A kind of superelevation insulation measurement instrument additive error electric current asymmetry compensation device, including signal source output VS、 Relay switch K1, current-to-voltage converting circuit, tension measuring circuit, the asymmetric double polarity of controller and two-way complementation it is accurate Variable voltage source;

The current-to-voltage converting circuit includes operational amplifier A and resistance RF, resistance RFBoth ends be separately connected operation and put The reverse input end and output end of big device A, the positive input ground connection of operational amplifier A;

The asymmetric double polarity precision variable voltage source of the two-way complementation includes variable voltage source VC1And variable voltage source VC2, variable voltage source VC1Output signal through precision resistor RC1It is supplied to the reverse input end of operational amplifier A, adjustable electric Potential source VC2Output signal through precision resistor RC2It is supplied to the reverse input end of operational amplifier A;

The signal source output VSFor generating driving voltage US, signal source output VSPass through relay switch K1Connect quilt One end of element DUT is surveyed, the other end of detected element DUT connects the reverse input end of operational amplifier A, operational amplifier A's The input terminal of output termination tension measuring circuit, the input terminal of the output termination controller of tension measuring circuit, controller generate Two path control signal is respectively supplied to variable voltage source VC1With variable voltage source VC2

Preferably, the variable voltage source VC1With variable voltage source VC2It is 16 digit mode converters, what controller generated Two path control signal respectively controls two 16 digit mode converters, forms two regulated power supplies.Preferably, the precision Resistor RC1Resistance value be 1G Ω, precision resistor RC2Resistance value be 10G Ω, variable voltage source VC1With precision resistor RC1String Connection forms first via compensating current element, variable voltage source VC2With precision resistor RC2Series connection forms the second road compensating current element, the The resolution ratio proportionality coefficient of compensating current element and the second road compensating current element is 10:1 all the way.

The device passes through signal source output V firstS, relay switch K1, current-to-voltage converting circuit, tension measuring circuit Superelevation insulation measurement system, the asymmetric double polarity precision variable voltage source of two-way complementation and tested member are established with controller The low-pressure side parallel connection of part accesses current-to-voltage converting circuit front end;Then before practical detected element measurement every time, according to accidentally Spill current compensation adjustment algorithm controls asymmetric double polarity precision variable voltage source, measures additive error electric current, works as additive error Less than one threshold value of electric current, which shows to adjust, to be completed, which depends on the resolution ratio and measurement accuracy with system;Finally, in practical survey When amount, according to insulation measurement algorithm, amendment actually flows through the leakage current of detected element and the insulation resistance of detected element Resistance value.

The superelevation insulation measurement instrument additive error electric current asymmetry compensation method of described device includes the following steps:

(1) driving voltage U is setS=0, and relay switch K1

(2) variable voltage source V is controlledC1With variable voltage source VC2Output be 0V, the output of recording voltage measuring circuit Value is Ve, then by Ie0=Ve/RFInitial additive error electric current I is calculatede0

(3) to initial additive error electric current Ie0Judged: if | Ie0| variable voltage source V is arranged in > 100pAC1Output Value is Ie0×RC1, recycle PI to adjust algorithm and adjust variable voltage source VC2, until flowing into the additional mistake of Current Voltage conversion module Spill current | Ie(t)|≤Ith;If | Ie0Variable voltage source V is arranged in |≤100pAC1Output valve be 100pA × RC1, recycle PI It adjusts algorithm and adjusts variable voltage source VC2, until flowing into the additive error electric current of Current Voltage conversion module | Ie(t)|≤Ith;Its In, IthFor given threshold;

(4) according to the output valve V of current-to-voltage converting circuita(i.e. the input value of tension measuring circuit) calculates compensated Remaining additive error electric current Ia=Va/RF

(5) closing relay switch K1, set driving voltage US, the output valve of recording voltage measuring circuit is Vx, then by Itotal=Vx/RFThe total current I for flowing into current-to-voltage converting circuit is calculatedtotal, calculated according to formula and eliminate additive error Effective leakage current I=I of practical inflow detected element after electric currenttotal-IaWith insulating resistance value R=Vx/(Itotal-Ia)。

The utility model has the advantages that superelevation insulation measurement instrument provided by the invention additive error electric current asymmetry compensation device and Method, using the bipolar offset current source of minimum resolution 0.01pA, maximum compensation electric current 50nA, for compensating additive error Electric current decreases to additive error electric current small;This method can rapidly and accurately solve the essence of small additive error electric current True compensation problem significantly improves superelevation insulation measurement resolution ratio, range and consistency.

Detailed description of the invention

Fig. 1 is the functional block diagram of apparatus of the present invention;

Fig. 2 is additive error current diagram;

Fig. 3 is additive error current compensation current source electrical schematic diagram;

Fig. 4 is that Current Voltage converts electrical schematic diagram;

Fig. 5 is the implementation flow chart of the method for the present invention.

Specific embodiment

The present invention will be further explained with reference to the accompanying drawing.

As shown in Figure 1, being a kind of superelevation insulation measurement instrument additive error electric current asymmetry compensation device, including defeated Signal source V outS, relay switch K1, complementary asymmetric of current-to-voltage converting circuit, tension measuring circuit, controller and two-way Bipolarity precision variable voltage source;The low pressure of asymmetric double the polarity precision variable voltage source and detected element DUT of two-way complementation Side parallel connection accesses current-to-voltage converting circuit front end;The variable voltage source VC1With variable voltage source VC2Output area be- 5V~+5V, precision resistor RC1With precision resistor RC2Resistance value be respectively 1G Ω and 10G Ω, variable voltage source VC1With it is adjustable Voltage source VC2The compensating current element that resolution ratio proportionality coefficient is 10:1 is constituted by the two precision resistors respectively.

As shown in Fig. 2, the electric current for flowing through current-to-voltage converting circuit includes flowing through the effective current of detected element DUT and attached Add error current;Additive error electric current is distributed ginseng mainly from background leakage current, the fixture electrical network of measuring circuit itself Extra current caused by leakage current caused by number, fixture and detected element contact thermoelectrical potential and leader cable friction electricity etc., Equivalent extra current is respectively Ik1And Ik2, total additive error electric current is frequently more than 10pA or more.

It is illustrated in figure 3 two-way precision adjustable current source generating circuit of the invention, 16 moduluses are controlled by microprocessor Conversion chip DAC8812 generates precision voltage source, then passes through R respectively120And R121Constitute asymmetric Precision Current Component.

It is illustrated in figure 4 Current Voltage detection circuit of the invention, flows through current input terminal, the two-way compensation of detected element Current source is coupled in parallel to the inverting input terminal of operational amplifier, and the feed circuit of operational amplifier is to be selected according to different electric currents The feedback resistive network selected selects respective feedback resistance by relay, and relay is controlled by microprocessor.

It is illustrated in figure 5 workflow of the invention, is included the following steps:

(1) driving voltage U is setS=0, and relay switch K1

(2) variable voltage source V is controlledC1With variable voltage source VC2Output be 0V, the output of recording voltage measuring circuit Value is Ve, then by Ie0=Ve/RFInitial additive error electric current I is calculatede0

(3) to initial additive error electric current Ie0Judged: if | Ie0| variable voltage source V is arranged in > 100pAC1Output Value is Ie0×RC1, recycle PI to adjust algorithm and adjust variable voltage source VC2, until flowing into the additional mistake of Current Voltage conversion module Spill current | Ie(t)|≤Ith;If | Ie0Variable voltage source V is arranged in |≤100pAC1Output valve be 100pA × RC1, recycle PI It adjusts algorithm and adjusts variable voltage source VC2, until flowing into the additive error electric current of Current Voltage conversion module | Ie(t)|≤Ith;Its In, IthFor given threshold;

(4) according to the output valve V of current-to-voltage converting circuita(i.e. the input value of tension measuring circuit) calculates compensated Remaining additive error electric current Ia=Va/RF

(5) closing relay switch K1, set driving voltage US, the output valve of recording voltage measuring circuit is Vx, then by Itotal=Vx/RFThe total current I for flowing into current-to-voltage converting circuit is calculatedtotal, calculated according to formula and eliminate additive error Effective leakage current I=I of practical inflow detected element after electric currenttotal-IaWith insulating resistance value R=Vx/(Itotal-Ia)。

The superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method that this case provides, can produce The bipolar offset current source of minimum resolution 0.01pA, maximum compensation electric current 50nA are incited somebody to action with to compensate additive error electric current Additive error electric current decreases to small;The accurate compensation that this method can rapidly and accurately solve small additive error electric current is asked Topic, significantly improves superelevation insulation measurement resolution ratio, range and consistency.

The above is only a preferred embodiment of the present invention, it should be pointed out that: for the ordinary skill people of the art For member, various improvements and modifications may be made without departing from the principle of the present invention, these improvements and modifications are also answered It is considered as protection scope of the present invention.

Claims (3)

1. a kind of superelevation insulation measurement instrument additive error electric current asymmetry compensation method is based on superelevation insulation measurement Instrument realizes that described device includes signal source output V with additive error electric current asymmetry compensation deviceS, relay switch K1, electric current Voltage conversion circuit, tension measuring circuit, controller and the asymmetric double of two-way complementation polarity precision variable voltage source;
The current-to-voltage converting circuit includes operational amplifier A and resistance RF, resistance RFBoth ends be separately connected operational amplifier The reverse input end and output end of A, the positive input ground connection of operational amplifier A;
The asymmetric double polarity precision variable voltage source of the two-way complementation includes variable voltage source VC1With variable voltage source VC2, can Adjust voltage source VC1Output signal through precision resistor RC1It is supplied to the reverse input end of operational amplifier A, variable voltage source VC2 Output signal through precision resistor RC2It is supplied to the reverse input end of operational amplifier A;
The signal source output VSFor generating driving voltage US, signal source output VSPass through relay switch K1Connect detected element One end of DUT, the reverse input end of the other end connection operational amplifier A of detected element DUT, the output end of operational amplifier A The input terminal of tension measuring circuit, the input terminal of the output termination controller of tension measuring circuit are connect, controller generates two-way control Signal processed is respectively supplied to variable voltage source VC1With variable voltage source VC2
It is characterized by: this method comprises the following steps:
(1) driving voltage U is setS=0, and relay switch K1
(2) variable voltage source V is controlledC1With variable voltage source VC2Output be 0V, the output valve of recording voltage measuring circuit is Ve, then by Ie0=Ve/RFInitial additive error electric current I is calculatede0
(3) to initial additive error electric current Ie0Judged: if | Ie0| variable voltage source V is arranged in > 100pAC1Output valve be Ie0×RC1, recycle PI to adjust algorithm and adjust variable voltage source VC2, until flowing into the additive error electricity of current-to-voltage converting circuit Stream | Ie(t)|≤Ith;If | Ie0Variable voltage source V is arranged in |≤100pAC1Output valve be 100pA × RC1, PI is recycled to adjust Algorithm adjusts variable voltage source VC2, until flowing into the additive error electric current of current-to-voltage converting circuit | Ie(t)|≤Ith;Wherein, IthFor given threshold;
(4) according to the output valve V of current-to-voltage converting circuitaCalculate compensated remaining additive error electric current Ia=Va/RF
(5) closing relay switch K1, set driving voltage US, the output valve of recording voltage measuring circuit is Vx, then by Itotal= Vx/RFThe total current I for flowing into current-to-voltage converting circuit is calculatedtotal, calculated according to formula after eliminating additive error electric current Practical inflow detected element effective leakage current I=Itotal-IaWith insulating resistance value R=Vx/(Itotal-Ia)。
2. superelevation insulation measurement instrument according to claim 1 additive error electric current asymmetry compensation method, special Sign is: the variable voltage source VC1With variable voltage source VC2It is 16 digit mode converters, the two-way control that controller generates Signal respectively controls two 16 digit mode converters, forms two regulated power supplies.
3. superelevation insulation measurement instrument according to claim 1 additive error electric current asymmetry compensation method, special Sign is: the precision resistor RC1Resistance value be 1G Ω, precision resistor RC2Resistance value be 10G Ω, variable voltage source VC1With Precision resistor RC1Series connection forms first via compensating current element, variable voltage source VC2With precision resistor RC2Series connection forms second The resolution ratio proportionality coefficient of road compensating current element, first via compensating current element and the second road compensating current element is 10:1.
CN201610884614.XA 2016-10-10 2016-10-10 Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method CN106483381B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201610884614.XA CN106483381B (en) 2016-10-10 2016-10-10 Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201610884614.XA CN106483381B (en) 2016-10-10 2016-10-10 Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method

Publications (2)

Publication Number Publication Date
CN106483381A CN106483381A (en) 2017-03-08
CN106483381B true CN106483381B (en) 2019-03-19

Family

ID=58269290

Family Applications (1)

Application Number Title Priority Date Filing Date
CN201610884614.XA CN106483381B (en) 2016-10-10 2016-10-10 Superelevation insulation measurement instrument additive error electric current asymmetry compensation device and method

Country Status (1)

Country Link
CN (1) CN106483381B (en)

Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008164375A (en) * 2006-12-27 2008-07-17 Sbc Co Ltd Device and method for measuring leakage current in electric apparatus
CN102590632A (en) * 2012-03-19 2012-07-18 常州工学院 Insulation resistance test circuit for circuit board
CN103308769A (en) * 2012-03-16 2013-09-18 三菱电机株式会社 Leakage resistance detection device for an on-board high voltage device and leakage resistance detection method therefor
CN103443646A (en) * 2011-01-21 2013-12-11 施耐德电气美国股份有限公司 Non-linearity calibration using an internal source in an intelligent electronic device
CN104283426A (en) * 2014-09-17 2015-01-14 矽力杰半导体技术(杭州)有限公司 Control circuit with multi-loop feedback and switching power supply with same
CN105049053A (en) * 2015-08-26 2015-11-11 清华大学 Complementary current circuit, switch circuit and current digital-to-analog converter of foreground correction
CN105811781A (en) * 2016-05-22 2016-07-27 中国轻工业长沙工程有限公司 High-voltage and constant-voltage signal source
CN107209217A (en) * 2014-09-26 2017-09-26 德利信电机株式会社 Leakage current calculating apparatus and leakage current calculation method

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2006275966A (en) * 2005-03-30 2006-10-12 Agilent Technol Inc Prober measurement correcting substrate, program thereof, and recording medium thereof

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2008164375A (en) * 2006-12-27 2008-07-17 Sbc Co Ltd Device and method for measuring leakage current in electric apparatus
CN103443646A (en) * 2011-01-21 2013-12-11 施耐德电气美国股份有限公司 Non-linearity calibration using an internal source in an intelligent electronic device
CN103308769A (en) * 2012-03-16 2013-09-18 三菱电机株式会社 Leakage resistance detection device for an on-board high voltage device and leakage resistance detection method therefor
CN102590632A (en) * 2012-03-19 2012-07-18 常州工学院 Insulation resistance test circuit for circuit board
CN104283426A (en) * 2014-09-17 2015-01-14 矽力杰半导体技术(杭州)有限公司 Control circuit with multi-loop feedback and switching power supply with same
CN107209217A (en) * 2014-09-26 2017-09-26 德利信电机株式会社 Leakage current calculating apparatus and leakage current calculation method
CN105049053A (en) * 2015-08-26 2015-11-11 清华大学 Complementary current circuit, switch circuit and current digital-to-analog converter of foreground correction
CN105811781A (en) * 2016-05-22 2016-07-27 中国轻工业长沙工程有限公司 High-voltage and constant-voltage signal source

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
一种宽量程高精度绝缘电阻测量仪设计;王晓俊 等;《电子测量与仪器学报》;20120215;第26卷(第2期);第155-160页

Also Published As

Publication number Publication date
CN106483381A (en) 2017-03-08

Similar Documents

Publication Publication Date Title
US8035396B2 (en) Method and device for measuring internal impedance of stationary battery
CN100429521C (en) Method of and device for insulation monitoring
ES2749449T3 (en) Method and device for testing a transformer
DE10106200C1 (en) Insulation monitoring method for unearthed electrical network uses pulses AC voltage applied between network and earth and evaluation of measured current values
CN103158576A (en) Battery current measuring and calibrating method and system
CN203502580U (en) Checking system for online insulation monitoring device
CN104698273B (en) Harmonic contributions division method and system
TWI380029B (en) Current-measuring device, testing device, current-measuring method and testing method
Sonerud et al. Dielectric response measurements utilizing semi-square voltage waveforms
CN1330967C (en) Portable potential difference meter
CN102841260B (en) DC microresistivity measuring system
CN104535839B (en) Photovoltaic grid-connected inverter insulation resistance detecting method and detecting device for implementing same
CN203720342U (en) Direct current magnetic bias automatic compensation device of metering winding of current transformer
RU2009135814A (en) Measuring the full resistance of the electric transmission line
CN104821552B (en) Excess temperature protection method, circuit and the linear drive circuit with the circuit
CN101806876A (en) Electronic type transformer checking system
JP6042220B2 (en) Inspection of measuring instrument system, corresponding measuring instrument system, and inspection system
CN205049678U (en) Short circuit testing arrangement is opened to camera module
EP2562553A1 (en) Low Frequency Impedance Measurement with Source Measure Units
CN103018575B (en) A kind of method utilizing large power, electrically sensing electricity testing device to measure high-power inductance
CN100371687C (en) Method of operating a measuring apparatus
CN103487767B (en) A kind of load driving circuits and electronic load
CN105958621B (en) One kind being used for capacitor group Bridge differential current protection out-of-balance current leveling method
CN202486269U (en) State tester of electrical equipment
CN201654130U (en) Automatic measuring and calibrating device of high-impedance measuring apparatus

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
TA01 Transfer of patent application right
TA01 Transfer of patent application right

Effective date of registration: 20190201

Address after: 210000 No. 2 Sipailou, Nanjing, Jiangsu Province

Applicant after: Southeast University

Applicant after: Nanjing Changsheng Instruments Co., Ltd.

Address before: 211189 No. 2 Southeast University Road, Jiangning District, Nanjing, Jiangsu

Applicant before: Southeast University

Applicant before: Nanjing Tong Sheng Instrument Technology Co., Ltd.

GR01 Patent grant
GR01 Patent grant